Syntax Magazine

SYNTAX

A PUBLICATION OF THE HARVARD GROUP

VOL. 5 NO. 11

ISSN 0273-2696

NOV- 1984

IN THIS ISSUE

IS TIMESTAR A DARK STAR?

Classified Ads . 10

Dear Editor . 6

Hardware Review . 4

Byte-Back Analog
to Digital Converter
for DC measurements
with your ZX/TS or
TS2068 and BB-1 con¬
trol module.

New Products and

Services . 2

News . 1

Speed and Style

in BASIC . 8

Measured data on
extra time required
to execute ZX/TS and
TS2068 programs with
varying subroutine
and FOR-NEXT loop
placement plus rules
to improve speed.

THANK YOU for all your
support, encouragement
and business. SYNTAX is
grateful to have so many
perceptive subscribers.

After months of very loud speculation, plenty
of wishful thinking, and innumerable missed
deadlines, where is the Timestar? What ever
became of the Trinity Magnum Co? Well, Timex
says they get the odd phone call, but no real
proposal, no funds to bind a deal, nothing to
regard seriously. In short, no negotiation.

SINCLAIR FORECAST

SYNTAX expects Sinclair Research to make some
moves before the end of Apr. 85. Recent rumb¬
lings in the rumor mill suggest it's grinding
up something. Production and quality issues
in the UK seem to be settling out. The CES
showing included several new non-computer
devices. UK magazines show Sir Clive's elec¬
tric tricycle. The Spectrum-i- trial balloon
floats across the US. Sinclair's quietly
talking to people in the US. This will all
coalesce soon — SYNTAX will keep you informed.

WILL JACKINTOSH JUMP ON QL?

Reports from CES in Jan. 85 suggest that Atari
will position it's 68000-based machine at the
same price as Sinclair's QL. Later news of
low earnings at Commodore suggest that they
will bear the brunt of Atari's 8-bit attack
early in the year and the 16/32-bit blast
later may find Commodore unable to respond.
This leaves the 16-bit MSX, Atari, and QL to
win your computer dollars later this year.

Index of Advertisers

Byte-Back . 9

E-Z Key . 5

G. Russell . 3

Despite technical and feature differ¬
ences of these machines, the battle will be
won on marketing and product positioning. On
the basis of experience, Jack Tramiel (Atari)
does not usually lose these battles, Sinclair
usually does, and the Japanese find a way to
change the game.

T-S Horizons

10

Why will it be different this time?

1

NEW PRODUCTS AND SERVICES

Tom Woods is so impressed with the
MSCRIPT word processor that he
sells it. Of course, Tom offers an
enhancement — available only through
him, & free with your MSCRIPT
order — for 2040 printers or TASMAN
interfaces. $69.95 From Thomas B.
Woods, POB 64 Jefferson, NH 03583.
603/586-7734 VISA/MC

Byte-Back offers new A/D converter.
See hardware review in this issue.
Also, they offer a Centronics
Interface for ZX/TS or TS2068. The
unit is cased, 5"Hx4"Wxl"T, & comes
with software for the computer you
specify when you order. The 4 1/2
foot printer cable is permanently
attached to the interface. This is
the only printer interface known to
us that provides an extender card
to attach other peripherals. Price
$84.95+$4.95 P&H from Byte-Back Co.
Rt 3, Box 147, Leesville, SC 29070
803/532-5812 VISA/MC

Also from Byte-Back, the MD-2B and
MD-68 modems with Smart Software to
send and receive programs by phone.
These modems include an RS-232 port
to drive your serial printer — no
separate interface needed. $119,95
kit or $149.95 assembled +$4.95 P&H

Tom Bent's 8K ROM modifications are
available from Tom Woods, an EPROM
that plugs into your ZX/TS & fixes
bugs while providing an exit to
your own LPRINT routine and much
more ($24.95).

" Powerful Projects with Your Timex/
Sinclair" offers you designs and
instructions for control projects.
This new (1985) book tells you how
to build a speech output module, a
power controller, an interface
connector, a temperature sensor and
other I/O devices. For each, you
get a schematic plus some hints on
construction. Photos and sketches
help you build these projects. In¬
cludes software descriptions to run

these devices. $12.95 , 256 pp. ISBN
0-673-18038-7 Author: Jim Stephens
Publisher: Scott, Foresman & Co.

1900 E. Lake Av. Glenview, IL 60025

" D. LIPINSKI SOFTWARE BUYERS GUIDE
TO SINCLAIR - TIMEX PRODUCTS & SER¬
VICES" contains 800 software ti¬
tles, 100 book titles, 100 hardware
items and services such as publica¬
tions. Data from 120 suppliers,
published in 3-ring notebook for¬
mat. Price includes first update
in Mar. 85. $20 PPD in US & Canada,

Overseas add $1.50 for surface, $5
for Air Mail. From D. Lipinski
Software, 2737 Susquehanna Rd.
Roslyn, PA 19001. 215/572-6812

SPEC-TAX (tm) for 1985 helps you
prepare your 84 tax return on your
2 068. Does 104 0 + most schedules,
not good for sched F. You enter
data as requested, 2068 computes
entries you make to tax forms.

Lets you enter multiple individual
items and then totals them for you.
Helps decide joint/separate returns
and standard/itemized deductions.

Use your 2040 printer to get hard
copy. $16.95 PPD from Poretsky and
Poretsky, Inc. 521 Argyle, Brooklyn
NY 11218. For info call 718/469-
5948 EVENINGS. Quantity prices for
dealers and user groups.

Brain waves control ZX/TS computer
to give 256 commands. Can control
a programmed english vocabulary
with print to screen, printer, or
voice synthesizer and can control
an external robotic device. Or use
Galvanic Skin Response unit to out¬
put % stress w / english sentences.
Can be used as talking lie detector
Send $5 for brochure or $19.95 for
book "Human Brain Waves to Elec¬
tronic Speech." Complete system w/
software $500. Rosetronix, POB 7464
Chula Vista, CA 92012.

John Meshna has 12 VDC green-screen
monitors for only $25 plus shipping
Call 617/595-2275 and get the new
catalog sent to you.

2

SPECIAL OFFERS END MARCH 30, 1985

N€UJ UF€ FOR VOUR TS2068?

V€S! uuith

ROMSUJITCH

Lets you run Spectrum programs on your TS2068!

* EASY INSTALLATION. No soldering, no drilling.

* Just plug inside your TS2068 freeing edge connector &
cartridge port for other uses.

* External Stick-on switch selects Spectrum or TS2068
ROM

* Thousands of good British programs available, many
from U.S. dealers incl. Us

Price $54.95 assembled/tested, U.S. shipping incl.
Canadians add $2., overseas add $5. shipping

SPECTRUM MANUAL - Sa*e excellent book packaged w. computer -
i«p. technical ROM info., SINCLAIR Basic Prgrsing. $10.95

ROMSHITCH + 007 SPY cassette proqra# 154.95 total (save $9,951
ROMSNITCH + NINKY BOARD 2800 - $69.90 total (save $8.)

If INKY BOARD 2 + NEW KEY cassette - $24.95 total (save $4.50i

UJINKV BORRD Cassette-Computer Interface

* Solves your LOADing problems.

* Duplicates ANY TS/ZX cassette

* User friendly. Simply plugs into cassette-
player & computer jacks.

* Makes UPLOADER use easy on TS2068.

UIINKV BOARD 2000 for TS2068, ZX Spectrum, TS1000/1500,
ZX80/81 Price $22.95 assembled/tested, shipping incl. to U.S./Can.
UIINKV BOARD2 for TS1000/1500, ZX80/81
Price $18.95 assembled/tested; $15. kit

SPECTRUM PROGRAMS NOW AVAILABLE with others soon to arrive:
•807 SPY: Must have back-up copier -7 seperate programs.

Copies all TS2868/SPECTRUM programs w/wo headers, stops
nachine code programs & sore! $9.95
•SUPERCODE 2: Superior Machine Code tool kit, 122 routines,
lost relocatable in your programs. User friendly. $19.95
•ASTRONOMY: Fun, educational utility for astronomers or
astrologers. Simulates night sky, calculates positions of
planets, comets, etc., plots constellations & sore! $19.95
•SOFT TALK 1: Utility to add digitized speech to your programs
from 78-88 word vocab.(eg. numbers, up, add, equal). $14. 95
•PINBALL WIZARD: Superb, colorful, fast-action graphics k
sound. A top British game. With 5 skill levels. $14.95
•6QLFIN6 WORLD: Series of interrelated games for 1-2 players.

Choose club, direction, speed of greens, etc. $14,95
•BRIDGE TUTOR 1 Beginners: 48 hands pre-dealt show fundamen¬
tals of bidding & card play. You bid k play cards. $14.95
•MIND GAMES: Chess, Backgammon, Draughts, Invader Cube $24.95
•WHITE LIGHTNING: SPRITES! Create fast moving graphics. Forth
& Basic based. Tutor incl. 2 Ca5settes:demo, develop. $24.95
•SPECTRE MAC MON: Macro assembler/editor, monitor/disassembler
Also useful to assemble code for CPUs other than Z80. $24.95

Information sheet, list of U.S./Can. retailers of Spectrum
cassettes, & our complete catalog free.

RUSSCll €l€CTRONICS

RD 1 * Box 539 * Centre Hall, PA 16828
814-364-1325 MasterCard/Visa 10am-8pm Check/MO

SPEECH RECOGNITION SYSTEM

* Train your computer to obey voice commands

* Recognizes up to 8 spoken words

* Includes speech amplifier unit, cassette program,
documentation

SRS2000 for TS2068
SRS1000 for TS 1000/1 500, ZX81
$32.95 assembled/tested; $27.95 kit

COMPCOOIER Power supply-Computer Interface solves most
overheating problems for TS1000/1500, ZX80/81 $6.95

HI RES GRAPHICS PIRNS - TS1000, ZX81 interface $5.

Utilities on cassette for TS1000/15000, ZX81

KEY - unlock, merge, renumber $9

HI RES PRINTER GRAPHICS $9

ZXLR8 Fastload (not for 1500) $10.50

Prices above include shipping to U.S./Can. i

TS1000/1500/ZX81 HI RES 16K CASSETTE PRQSRAHS-resolution sase
as TS206B without any hardware. See to believe!

ROCKET MAN - action gaae $9.95

FORTY NINER - action gases based on CA. gold siners $9.95

TIMEX 16K RAM PACS Tor TS1000, ZX81 - $25. shipping incl.

HARDWARE REVIEW

Product: Analog-Digital Converter

Machines: ZX81, TS1000, TS2068
Price: $29.95 + $4.95 P&H
From: Byte-Back Co.

Rt 3, Box 147
Leesville, SC 29070
803/532-5812

Used with your BB-1 I/O board,
this converter outputs 255 at 0 V
down to 0 at the full-scale input
voltage and puts the data in memory
You then read it out by peeking a
memory location and use the data in
your program.

Housed in a plastic tube about
1 inch in diameter and 4 1/2 inches
long, this converter plugs atop the
BB-1 with a built-in 50-pin connec¬
tor. An RCA jack at the left end
accepts the DC voltage you wish to
measure, and a pushbutton at the
right end resets your converter at
start-up. Eight DIP switches,
accessible through the front, set
one of five full-scale ranges:

0.25 , 0.5 0, 2.75 , 5.00, or 10.0 VDC
positive only. You can't open this
device — it's epoxied together.

SYNTAX made only simple tests
of operation on two ranges — 2.75 V
and 5 V. In both cases the device
behaved as we expected, based on
the manual which comes with it.
Except for the 10-Volt range, each
full-scale value is individually
calibrated by Byte-Back for your
converter. Our 2.75-V range is
actually 2.78 V; our 5 is really
5.02. Since all SYNTAX'S tests
used a 1.5 V battery, we saw only
the lower part of these scales.

Our converter consistently
reads lower than the digital volt¬
meter by an amount that grows as
the DC input increases. Thus, at
1.488 V input, the computer said we
had 1.437 volts on the 5-V scale —
about 50 millivolts low. But at
0.522 V input, the computer read

0.519 V, only 3 mV low. Similarly,
the 2.75-V scale read 42 mV low at
1.492 V input and 9 mV low at 0.521
V input. Since 8-bit resolution
only measures within 0.5% of full
scale, these are reasonable errors.

Keep in mind that this A/D can
only choose 1.471, 1.482, 1.493, or
1.5 04 when the input is 1.492 on a
2.75-V scale. Those are the 8-bit
steps — spaced 0.0109 Volts apart.
Similarly, resolution on the 5-V
scale amounts to 0.0197 Volts. So
you could probably get 2% accuracy
with 0.5% resolution from this A/D
at fixed temperature. Neither we
nor Byte-Back express any opinion
about temperature stability.

Since this device has parallel
output, you use all input lines of
your BB-1 when you connect the A/D.
If you need digital inputs as well,
you need another BB-1. But you can
still use 8 digital outputs. In
fact, you can use some to connect
the converter to multiple inputs.

Well then, what use can you
make of this device? Try it for
applications where voltage changes
are a few percent or more, but over
a long interval. Or where fluctua¬
tions of your signal play a bigger
role than the value. For example,
a voltage in a piece of equipment
with an intermittent problem.

Generally, this type of device
serves best for automatic input of
medium-accuracy data. For example,
reading a voltage every 30 seconds
for 4 hours or hourly for 7 days.

For best accuracy, store and
process the bytes from the A/D.
Then convert only the answer to the
appropriate units.

Related reviews include the BB-1
Module (Jan. 83, p. 8) and the Votem
A/D (Oct. & Dec. 82). Votem is a
0-1 V input, serial output A/D that
connects through the cassette jack.

4

CAT. NO.
MD1

TPIF

TW2

TSW

UP2

FL1/FL2
SO 02
0002

OOS/DD

FDS1

SP DOS

OOF

F0S2

GLP

KBO

MLP

VC/VF

GT2

CB2

JRC1

JRC2

JRC3

ML

ITEM

2050 MODEM with Smart I Software (or TS1000 or 2068 *119.95 4 *500 S A H

Designed especially for all TIMEX computers, the 2050 offers some exceptional features at a remarkable price. It's one of the new "Modular” hook-up modems Just plug the modem into your phone jack. The
standard SMART I software that comes on cassette will allow you to use the 2050 with TIMEX 1000, 1500, and 2068 computers and provides the capability to auto-dial and auto answer as well as access any outside

(Jala DdSe

SMART II Software for 2068 4 K s 4 H

The optional SMART II software comes on cassette and provides auto-dial of up to 10 different phone numbers, each with it’s own preset access codes and log-on sequences! You can save and load other files
containing phone numbers and other communication parameters making the auto dial feature capable of many more than the basic 10 numbers. It will also upload and download to and from memory.
TASMAN PRINTER INTERFACE lor 2068 waoo $ $2 95 S 4 H

A Centronic standard parallel interface which includes a 3-foot cable. LList and “LPRINT" software. Also includes FAST M/C, Hi-RES screen copy routines available for the
Epson, Star Seikosha (Gorilla Banana), Centronics GLP and Radio Shack color printers IN COLOR "M

TASWORD TWO WORD PROCESSOR for 2068 $49 95 4 1 95 S 4 H

. .. 17,6 Passional standard word processor for the 2068 computer systems. A superb word processing program which is equal to Wordstar* (some say better). Interfacing is a cinch since Tasword Two drives
full-width printers via the Tasman interface. NOTE: You can also use this with the TS2040 Printer!!

SI 9.95 A SI. 95 S A H

TASWIOE PRINT UTILITY lor 2068

Allows your “BASIC” programs to output the display in 64 columns to your TV or printer!

UPLOAD 2000 SHU* A 195 SAM

Ji'000,10 TS2?!i? Pr°.<lrTe^2Ve^r , ™s new program allows you to convert your library of ZX81, TS1000. and TS1500 programs into TS2068 programs! Now you don’t have to rekey all those programs to
make them compatible with TS2068s. It works for programs written in BASIC, not machine code. Due to the difference in recording methods used, we recommend the use of a filter (FL1000) when loading TS1000
programs into your TS206o.

FL1000 (Filter for TS1000 Tapes - FL2000 Filter for TS2000 Tape - Please specify - FL1 or FL2) n or x 1 « « x u

5'/a - Inch SINGLE FLOPPY DISK DRIVE (Shugart compatible) 11700?* m'S « x u

5-/4 ■ Inch DUAL FLOPPY DISK DRIVES (Shugart compatible) ,29*95 A 10 00 S A H

. , CL0,SfE °i!T SALE ' bra{? new sin9|e-sided' double-density Dual Floppy Disk Drives that includes power supply on/off switch, case and fan. (NOTE: You must supply the required controller board and cables
to complete the system.) These can operate as single-density drives and can be used with other computers.

DOS CONTROLLER BOARD A CABLE for TS1000/1500 *199 95 A 5 00 S A H

F*trpTm!i!bfact i^'h08 C?^SAVE * L0AD!° d'Sk?r ?SSett typC fr°m T/S BASIC commands usin9 this COMPUSA Controller board. Data files can be created using READ & WRITE physical track commands
Extremely fast-loads a 32K program in 1 second. Extremely reliable - all files read & checked after beinn written r.nmp with 'o nano manual . Piirrh»a can<»«alu (nr tmnn

FLOPPY DISK SYSTEM for TS1000/1500

Complete Dual Floppy Disk System. Includes DDD2 and DOS/DD above.

FLOPPY DISC INTERFACE for 2068

SP-DOS offers these operating features: Loads 32K per second, Stores 820K per disk, 4 drives max.

QUAD DENSITY FLOPPY (Required for Drive #1) 820K

FLOPPY DISK SYSTEM for 2068 (Complete Floppy Disk System includes: SP-DOS and QDF, as described above.)

80 COLUMN CENTRONICS GLP PRINTER

Ideal for word processor above. Has both Draft and Near Letter Quality modes of printing. Handles cut sheet, roll and fan fold paper
KEYBOARD for TS1000 *59.95 A *4.96 S A M

.. miSrvk7b0aICl does not have a case. The same key switch is used as is found in the expensive computers, such as: Hewlett Packard, Texas Instruments, Atari, DEC, etc. Multi-colored key caps are used with
the TIMEX legends. It also has a space bar and six spare keys. No soldering required, as it just plugs into the computer board.

MACHINE LANGUAGE PROGRAMMING ON THE TS1000 and TS1500

This 250-page book describes how to do machine language programming within the environment of the T/S ROM.

VU-CALC and VU-FILE (The Organizer) Getting Serious With Your TIMEX/SINCLAIR

This new book describes how to inexpensively use Spreadsheet and File Management programs.

GRAPHICS TABLET lor TIMEX 2068 (Interface and Software, and a 32-page Owner's Manual, ZebraPainter Quick Reference Card)

COLORING BOOK SOFTWARE for above. (Allows screens to be displayed like a coloring book, then painted using only the NDALA Pad)

SUPERTAPE for TS1000 and TS1500

Has 45 programs, including: Secret ROM routine, Super f(n) plot, four 2K action games, Touch Type Teacher.

COMPASS (Two Programs on one tape) 2068 INTEGER BASIC COMPILER (Limited Basic Set) and 2068 TWO PASS Z80 ASSEMBLER

SIX 2068 PROGRAMS ON ONE TAPE (Text Edit) - Touch Type Learing Game, Hi-Res Lander, Three Game Pack, Oscilloscope, The Great Graphics Show.

MAILING LIST for 2068 7 Fields, Can Search/Sort/Delete/Add by fields.

SOFTWARE for ZX81/TSI000/TS1500 @ *8.00 each A *2.00 S 4 H or 5 for *25.00 A *3.00 S A H. or 10 for *40.00 A *4.00 S A H QUANTITIES LIMITED -Specify a second choice when ordering!

Send *1.00 for a fully descriptive SOFTWARE catalog.

1 second. Extremely reliable - all files read & checked after being written. Come with 32 page manual - Purchase separately for $10.00 - refundable.

*429.95 A *10.00 S A H

*199.95 A 3.95 S A H

*289.95 A 7.95 S A H
*449.95 A 8.95 S A H
$299.95 A 5.00 S A H

*14.95 A *1.95 S A H

$19.95 A *1.95 S AH

*119.95 4 *2.95 S AH
$1*95 A $1.96 S AH
*24.95 A *1.95 S A H

*24^5 A *1.95 S A H
*24.95 A *1.95 S A H
*24.95 A *1.95 S A H

Prices and availability are subject to change without notice. Call or write for current prices. Prices expire one month after publication Maximum S A H charged is $10.00 per order.

Hardware carries Manufacturer's Warranty and our 10-day money back offer. Returned items must be in new condition and in their original containers with all instructions and documentation otherwise thev
will not be accepted. Software is guaranteed to load. Defective tapes will be exchanged only. ’ mcy

USE THIS ORDER FORM:

□Check MO DVisa □MasterCard F©b. 1, 1985
Card #

Exp Date

Send to

E-Z HEV

Suite 75, Dept. STX
711 Southern Artery
Quincy, Massachusetts 02169
(617) 773-1187

Qty.

Item

Unit Cost

Item Total

S&H

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Sub totals:

Mass, residents add 5% sales tax

Grand total:

Signature

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.State _ Zip

Dear Editor:

Many users that I know share a
single complaint. US vendors for
the TS2 068 (as well as ZX/TS) don't
advertise their products in any US
Timex-Sinclair publication and,
after we hunt them down, they don't
deliver for months. Worse, they
don't tell us when they'll deliver
or warn us of delays. I mail-order
software from England and have it
in my hand in two weeks.

Some vendors don't even order
the merchandise until they have our
money — but they don't say this up
front. When we write, we get no
answer. If they even have a listed
phone, they don't answer. If they
have an answering machine, they
don't call back.

As an industrial engineer I
buy machines that take six months
to deliver, I can deal with delay.
But don't tell me you need two
months and then take six. I waited
from Jan. to May for a modem, then
cancelled the order. In June, the
company shipped it anyway and I
refused it.

Our members are subscribing to
English magazines to find ads for
software we can buy and use. Good
stuff, not trivia. Shipped, not
vaporware. Serviced, not ignored.
There are vendors who want our
business, we'll give it to them.

Bob Dyl, Director
Ocean State Users Group
Newport, RI 02840

SYNTAX shares your concern for the
rude (and often illegal) behavior
of some vendors.

Locate & support the best &
treat them honestly. Pay for what
you use without exception. Three
large UK software houses (Imagine,
Rabbit, & Carnell) failed, despite
product excellence, because of

rampant copying. Sinclair User
magazine reports a class of 26, of
whom 17 own computers. All had
copied a game, only 3 had ever
bought one — KO.

While John Slattery's system
(VU-CALC review JUN.84 p 5) works,
you can SAVE less and still have
the necessary parts.

First, add CLEAR as the first
command in line 32 00. Then you
SAVE "vc" CODE 29327,7000 to store
the original MC program without
data. You don't need the SCREEN?
material it serves no computing
function. (SCREEN? occupies 6912
extra bytes on the tape — KO)

Also, the program does not use
all 37K without data. The BASIC
part takes about 3K. The MC needs
a little less than 7K — most space
above RAMTOP holds data.

I modified line 10 and added
line 9990 as shown here:

10 CLEAR VAL "29327": BORDER L
N PI: PAPER LN PI: INK 9: CLS :
PRINT FLASH l;"Leave Tape Runnin
g as vcalc2 is being loaded.": L
OAD " vc "CODE : GO TO VAL "3200":

REM RLP mod 9/19/84

9990 SAVE "vcalc2 " LINE 10: REM
rip mod SAVE "vc"CODE 29327,7000

Does anyone know how /we can
create 8-character vcalc columns?

Robert L. Pekar , Columbus, IN 47201

I need to erase a MC routine,
stored above RAMTOP, so I can use
the space. For example, I use a
fast-load program to load a large
application program. The fast-load
sits above RAMTOP, mine sits below.
When big arrays are DIMmed, I run
out of space. How can I clear the
memory, but not lose my program?

H. Olsen, Prince Geo, BC V2N 2B2

6

You must move RAMTOP and ERR SP by
poking the system variables, then
execute 8 other pokes to recreate
the 4 bytes just below RAMTOP at
the new location & clear them from
the old. You'll find the recipe to
expand memory after a LOAD in the
Jun.82 SYNTAX, p.15, with a crucial
correction in Apr. 83. Dave Wood
gives a MC routine to move RAMTOP
without erasing memory in his new
book ML PROGRAMMING ON THE TIMEX-
SINCLAIR (Reviewed Oct. 84).

Before you expand the memory,
you should POKE zeros from RAMTOP
to the end of memory with a loop in
BASIC, or write a small MC routine
to do this. Dave Wood comes to the
rescue again on p.64 of his book,
showing how to use a ROM call to do
this cleaning. — KO

I'm having two problems trying
to use the program for ZX/TS Home
Budget (from SO, Spring 83) on my
2068. It won't auto-RUN, nor will
it SAVE properly once my variables
have been entered.

D. Brumfield, Jr, Roselle, IL 60172

Change line 9900 to the 2068
format SAVE "HOME BUDGET" LINE 100
(or wherever you want to go) and
get rid of 9905. My guess is this
change will cure both problems — KO

When I attach my 2040 printer
to my ZX-81, and attach my 16K RAM
I get only 8K of memory. Without
the printer, it's fine. I've tried
several computers and RAM packs; my
problem follows the printer.

Peter D. Aronson, NY, NY 10036

You really know two things here —
the problem is with the printer and
it's related to address, not data.
You almost certainly have a shorted
address line. It's above A8, since
the IK is unaffected, and below A14
& A15 which play no role with a 16K
RAM. Look for a short on A9-A13.

Since all keys work (judged by the
your sample program) I guess two
address lines are shorted together.
An open address line at the exten¬
sion connector would also reduce
the memory addressed.

Look for loss of shifted key
functions in one or two half-rows
when the printer is on the system.
Shorts should affect the keyboard
as well as the RAM. Opens leave
the keys unaffected.

Try a program to find missing
addresses. Convert these to binary
values and look for bits that don't
change. This will identify a spe¬
cific address line and thus one pin
on the connector.

Look in the Connector first,
then inside your printer. If you
diagnose an open, the problem can't
be inside the printer — it must be
in the connector on the printer — KO

I get no color with my 2 068 on
my Amdek C 300 monitor. They tried
the monitor and they say it makes
fine color. Amdek says the monitor
jack on my 2 068 may not be working.

Do I need some adapter between
the monitor jack and the monitor?
Could it be the cable?

Va. Stojanov, Mt. Laurel NJ 08054

TS 2068 color signals are not up to
standard and may not work with some
monitors and TV's. We have no word
that Amdek monitors work, but the
Sears TV/monitor definitely does
work. Try your computer on one of
these in the store. Use the cable
you have now. If it works on both
TV and monitor, you know the Amdek
is the problem. If not, your 2068
needs repair, send it to the Timex
Little Rock address in your manual.

Readers with information on TV
and monitor performance with TS2068
computers may share it through
SYNTAX. We'll publish a list.

-7

STYLE AND SPEED IN BASIC

When you write a BASIC program, the
order in which you carry out your
tasks affects the speed of your
program. This routine lets you see
simple examples that show how the
same task can take 42 seconds at
the front of a program , but 78 at
the end. When you've seen these
results, you may rethink your
notion to put a screenful of REM's
at the start of your program.

ADDITIONAL SECONDS REQUIRED FOR
5000 GOSOBS AT SELECTED PLACES

1

1

1 TOP

CALL TO

_ MID

BOT

1

TOP| X

+6

+11

CALL |

MID |+12

+18

+2 3

FROM |

BOTl+25

1

+ 31

+ 36

Your 2068 and your ZX/TS (in
FAST mode) take the same additional
time for these tasks. For 2068's,
X=42 seconds. In FAST, ZX/TS's
take only 35 seconds because they
use no time to control the screen.
In SLOW mode, ZX/TS's will take 5-6
times longer — both the fastest time
and the penalty get magnified.

SYNTAX measured these results
using the listings reproduced here.
Note that content of program lines
is irrelevant — only the number of
lines to skip affects the time.
Also, these programs are not long,
but we traverse them many times.

You can rerun these tests with
your changes. We just changed the
target of the GOSUB to 10, 700, or
1000 as desired. We always started
with a clear screen and began the
run with GOTO 2 , 2 00, or 2 000.

we deleted lines 3, 300, and 3000,
then tested. Sure enough, loops in
the middle took 6 extra seconds and
loops at the end took 11. Again,
the 2068 came out a second slower.

SYNTAX suggests the following
rules to make your programs faster
when that's your goal. Remember,
speed costs readability.

o Locate setups, REM's, and
seldom-used pieces at the end.

o Put often-used items and
their calling routines at the front
o Minimize the number of pro¬
gram lines preceding loops.

o Trade complex instructions
for fewer lines preceding loops.

o Avoid subroutines called a
lot by a loop near the end of the
program — repeat the code in the
loop instead.

Program shown runs on ZX/TS. For
2068, use lower-case variables and
get a Syntactic Sum of 17683.

Next we wondered if FOR-NEXT
loops would take variable times, so

8

BYTE-BACK modules

164-K MEMORY

/ JF ’ - \ me Jules Carry

/ /M’0 ■‘r — v
/4^w\

\w&/ A)

w/// A

xaa a /

vv /

MD-2 SMART MODEM
$119.95 KIT

ASSEMBLED AND TESTED $149.95

WITH NEW SMART, Menu Driven SOFTWARE
Included FREE.

• Send and receive Programs by Phone

• Copy Information into memory from a Host
Computer (such as CompuServe), Print it, Review
it, Save it on tape.

• Send Text from Memory

• Use Timex 2040 Printer or Any RS-232 Printer

• RS-232 Printer Port provided.

• No need to buy a separate RS-232 Module to
Drive your Serial Printer

• No extra memory Required, But with 64-K
Memory You Can Store Up To 60 Full Screens

Use your phone to connect your “LITTLE" computer to th^
“LARGEST” computer networks in the world

Order the MD-2B for your TS-llll

Order the NO-48 for your TS-2048^AfJ i

PARALLEL PRINTER INTERFACE

Tie your Tinex Sinclair to i S84 • 95
full size parallel printer. ' %

Cable and software included. u"'*i *”J

W/f/7 Battery Back_up(fc «f AA 95

$11*. •* ASM MOLED & TESTEO ^ | ^ g(J

the “ULTIMATE MEMORY ,

UM-64 NOt avai ^ ' * tk( Ts“28<8

FEATURES:

• Battery Backup - Computer and full 64-K Backed

• PROM/ROM socket

• Reset Switch-Reset without destroying Program

• BYTE-BACK EXCLUSIVE FULL 64-K

The 0-8K area is available You can execute a copy routine (provided) to
copy the TIMEX ROM into the 0-6K area of RAM then flip a switch and you
have your operating system in RAM You can modify it and create your
Own customized operating system

CONTROL THINGS WITH
co YOUR COMPUTER

BYTE-BACK’S BB-1
CONTROL MODULE

$59 00

INSTOCK!

WIRED and TESTED $69.00

• 8 Independent Relays

(with LED status indicators)

• 8 Independent TTL Inputs

( with Schmitt trigger buffers

ANALOG-DIGITAL CONVERTER <A-D>

Plugs into your BB-I and allows *29 ok
_ your caaputer to mature voltages * 3

CompuServe SPECIAL! ! !
- HOUR

S reg. *59.95 NON *29.95

UM-64 wired and tested . $119.

U1-44 Kit . $119.

BB-1 wired and tested .......$49.

BB-1 kit . $59.

RS-232 wired and tested . $49.

RS-232 kit . $59.

ND-26 wired and tested . $149.

ND-2B kit . $119.

ND-48 wired and tested . $149.

MO-48 kit . $119.

lease specify computer type

_ A-D converter for BB-1 . $29.95

_ Test Lead for A-D converter ..$3.95
_ Parallel Printer Interface ..$84.95
_ Conpuserve Package . $29.95

- Cable for RS-232 . $19.95

SOFTWARE

- Printer Software for RS-232 .$29.95

. ZX PRO/FILE (TS18BI) . $14.95

- ZX PRO/FILE (TS2I48) . $29.95

Syntax

Shipping and Han dingS H6

ORDER PHONE (803) 532-5812
Bill My □ Am. Exp. □ Visa □ M/C

Card No - - - . Exp. Date _

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Address _ _

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CHECKS
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CLASSIFIEDS

**ZX-TEXT** 16-64K, 1300-6500 Words
Write, Read/Edit, Print, Save, Clear
Text. Full/Window-Screen Read/Edit:
$19.95. **ZX-CALC** 32-64K, 15X30
matrix, 8 chr/cell,Str labl ,valu,f r ml
All ZX81 fnctns, Cursor ent,dlt,algn
Vert wdwg,Abslt/Reltv replctn, SUM/
Autocalc fnctn,Comptbl ZX/TS prntr:
$19.95. A.F.R. SOFTWARE-1605 Penna.
Av. ,204 , Mia. Bch, FI. 33139. +FL si tax

FASTFILE Professional Data Manage¬
ment System files anything quickly.
Sorts 1500 5-byte records in 24 sec
500 in 3 seconds. Searches Through
1500 records in 1 sec. Adds up 1500
decimal numbers in under 2 seconds.
Write for more info or send $19.95
+ $2.00 P&H to: TOM COLE
1314 Speight #15 Waco, Tx 76706

Thomas B. Woods has a big new cata¬
log with lots of brand new products
NEW 8K ROM upgrade, Mscript WP, ZX
Pro/File, Prowriter printers, Tas¬
man interfaces and much much more!
Send $1 (refundable) to:

Tom Woods Box 64 Jefferson, NH 03583

**** GAMES FOR THINKING PEOPLE ****
For ZX81 or T/S1000, 16K or T/S1500
KARTIK tm A crossword card game for
2-8 players. Words scored across,
down or diagonally. Lots of fun,
and educational!

TANGLE4 tm A new patented strategy
game for 2-4 players. Uses board
with hidden random directions of
movement revealed by pieces. Will
test your ability to think ahead.
INTR SPECIAL $15.00 ea. ( r eg . $ 1 9 . 9 5 )
+ 6.5% tax (CA residents) +$2 S/H.
Cassette or A&J Micro Drive Wafer.
Check or MO to: Willcocks Research
Consultants, 6321 W. 78th Place,

Los Angeles, CA 90045.

NEW INTEGRATED DATA SYSTEMS ADDRESS
Specials: $40 TS1000, $25 TS 16K,

$80 TS2040. P&H $5/ord or $1.50/
RAM. Cheque/VISA/M/C. Catalogue $2
416/463-5510 Answering Machine
35 W. Av, Suite B, Toronto M4M 2L7

SERIOUS BUSINESS SOFTWARE for ZX81,
T/Sl 000,T/S15 00. Send S.A.S.E. for
catalog to: A.F.R. Software, 1605
Penna. ,Av. ,2 04 , Miami Beach , FI . 3315 9

FISHFINDER analyzes season, weather
& solunar tables. Tells when, where
& how to catch fish. Authored by No

woods guide 30+ yrs. 2068 21.95

SPECIAL PURCHASE (While they last)
TS 1000's 29.95

TS 1500's 49.95

TS 2068's 119.95

TS 2040's 89.95

TS 16K Ram Packs 19.95

Prices include shipping/handling
BUDGETSOFT, 230 N Main Street
Rushville , IN 46173 VISA/MC/CHKS

COVERED ZX FEEDTHROUGH CONNECTORS
Connector, extender circuit board,
cover with side cable exit & screws
as used on MW-100 printer. $10 ppd
In stock, new— ORDER FROM SYNTAX.

Each issue brings you 32 pages of usable in-formation, program
listings, product reviews, programming articles, hardware
projects, and applications -for your computer. T-S HORIZONS
■features nationally known authors like Paul Hunter, Gordon
Young, and others. The price is ONLY $15.00 -for a -full year
(12 issues). AND -for a limited time only, new subscribers
will receive our special telecommunications issue (#7, see
below) *FREE* with their subscription.

T-S Hirixinx

A It o' dab** Quality lor Itta Time, Compute! Uset

Ai(«t MT SL2S

PROGRAMS BARR SWITCHING -4

TIPS “ WORM "• CONCLUDED

REVIEWS POWER SUPPLY?

R nn« r s A Gwiii Nee Celaaa

IN T-S HORIZONS *7
Byte Back Modem Review
2068 Programming Tips
How a Compiler Works
Tel ecommumi cations
•for Beginners
Book & Game ^Reviews
Rotating Globe Routine
Articles By 'G . Young
and Paul Hunter
Sinclair In-fo. Network
TS-1000 Power Supply

-and more 1 1 1

T-S HORIZONS

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_ 1

lO

SYNTAX is published monthly by a wholly-

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Syntax ZX80, Inc.

RD 2, Box 457, Harvard, MA 01451.

Telephone 617/456-3661.

Publisher: Kirtland H. Olson
Editor: Eric K. Olson
Consulting Editor: Ann L. Zevnik
Technical Consultant: Kirtland H. Olson

© Syntax ZX80, Inc., 1984. All rights reserved.
Photocopying prohibited. ISSN 0273-2696

OUR POLICY ON CONTRIBUTED MATERIAL

SYNTAX invites you to express opinions related to any Sinclair or Timex com¬
puter or peripheral, or the newsletter. We will print, as space allows, letters discuss¬
ing items of general interest. Of course we reserve the right to edit letters to a
suitable length and to refuse publication of any material.

We welcome program listings for all levels of expertise, written in either Sinclair
BASIC or Z80 machine code. Programs can be for any fun or useful purpose. We
will test run each one before publishing it, but we will not debug programs; please
send only workable listings. Ptograms submitted on cassette can be tested more
quickly and with less chance of error.

In return for your listing, we will pay you a token fee of $2.00 per program we
use. This payment gives us the nonexclusive right to use that program in any form,
world wide. This means you can still use it, sell it, or give it away, and so can we.

We will consider submissions of news and hardware or software reviews. Please
keep articles short (350-400 words). Again, we reserve the right to edit accepted
articles to suitable length. We will pay 7 cents per 6 characters, including spaces and
punctuation, for accepted articles.

When you send in articles for possible publication in SYNTAX, please include
the following information:

• How to operate the program, including what to input if it does not contain
prompts.

• Whether you can run the program over again and how.

• How to exit the program.

• The Syntactic Sum (program published in June 81;
send SASE for a free copy).

• What RAM size program requires

• What ROM program uses (8K, 2068, Spectrum).

• For MC programs, what addresses must change to relocate the code and what
ROM calls are used.

We pay for this explanatory text at the same rate as we pay for articles in addi¬
tion to payment for the program itself.

If you want us to return your original program listing or article, please include
a self-addressed, stamped envelope. Otherwise, we cannot return submitted material.

DEADSOFT (TM)

Up to now, hardware freaks had
all the fun. No more — now software
junkies get an even break. SYNTAX
offers you broken software to fix
or use for parts in your projects.

"At these prices we can't test
'em." But it's the software that's
bad — the tapes are fine. High-
class stuff by famous authors, but
production messed up. Load it, fix
it, get working stuff and save big.
We'd charge more for educational
value, but the boss wants these off
the kitchen floor, so out they go —
cheap. Buy extras to give smart-
mouths who call your ZX/TS a toy or
put down your programming skills.

TITLE _ FUNCTION _ PRIGS

VIDEO PLAN* SPREADSHEET 39.95
INVENTORY FILE MANAGER 49.95
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COMPUTACALC* SPREADSHEET 39.95

* Reviewed in SYNTAX Mar. 82

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Send us a copy of your SN label and
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of SQ magazine with the great John
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programs like the Federal Income Ta
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Remember, many ZX/TS programs work
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OFFERS EXPIRE 31 MAR 85

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INVENTORY CLEARANCE

The ZX81/TS1000 Home Computer Book
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Hill, ISBN 0-88134-106-1. Worth it
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way to combine BASIC programs from
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